Continuation of HAC 101, emphasizing the construction of equipment, systems, controls and accessories found in refrigeration and air conditioning unit systems. Special emphasis is given to servicing, repair, testing, installation, charging, reading and wiring from ladder diagrams, and troubleshooting. Emphasis will also be placed on charging and working with non ozone depleting refrigerants. Repeatable to eight credits. (1.2) Proficiency Credit Available (3 LETSIR) Pass/No Credit Not Available